Electroplating apparatus



E. L. A. CAMlN ET AL.

ELECTROPLATING APPARATUS 2Sheets-Sheet 1 Filed May 8, 1944 9 W9 E. L. A.cAMlN ETAL ELECTROPLATING APPARATUS 2 Sheets-Sheet 2 Filed May 8, 194.4

JNVENTOR Etienne LA. C'czmzn Fig. 3

)ymymays Patented Jan. 31, 1950 2,495,695 ZELECTROPLATING APPARATUSEtienneLLA. Camin and Herbert Kenmore; New York, N. Y, assignors, bymesne assignments, to Kenmore Metals Corporation; New; vYork, N. Y.,acorporation of Delaware Application May 8, 1944, serial No. 534.543

' Thisinvention relates to a novel apparatus for providingelectro-chemical deposits, platings or coatings on acoiledmeta'llic-body and the apparatus forproducingthe I same. Morespecifically this invention =relates 1:0 an apparatus by which a coiledspring like metal body as of 0010- per or the like 'may be passedthrough a series'of preparatory plating baths and post platingtreatments rapidly while 'depositing ther'eon excellent and, relativelythick metal plating.

Previously metal wire hasbe'en plated, for example, by passing a verythin metalwire of about .0I""diameter through oneor a series of baths,the wire being travelled through the bath byibringingsit. downto guide'rollers, out of the bath and into subsequent baths while as muchelectrical load was applied tothe wire as the wire was capable oftaking, this being determined prlmarily. byits diameter. In order tolead the wire through these difierent rollsyit is'necessary that thewire be very thinso as to be 'sufilcientlyipliable. Because to bepliablesuch wire must be very thin; only;arelativelyz smallelectrical'load can be applied and a thin metal'plating obtainedthereon. Ifa thick metal coat is desired; the time necessary to obtainsuch coat is impractically long.

-It has therefore -been the practice to :run' a great number of suchwires simultaneously through such baths and the ordinary productionofsuch fine wire on a large'machine such as presently usedin thisindustry constitutes a relatively small amountrunning-v in only tens 'ofpounds per day production.

It is mechanically impossible to force a wire of heavy gauge-annealed ornot,to take theshape which is necessary to make it travel continuouslythrough such asequence of operations which are required to obtain acorrect plating;

Itis the object of the present invention to provide amethod-andapparatus whereby a heavy gauge-wire iscarried through a series ofbathsand electroplated asidescr-ibedhereinafter and to redraw by conventionalmethods such plated wire to any desired gauge as fineas anyordinarywirecanbe drawnr I It is'an additional-object of'the-present invention toprovide -a mechanicalworking I of the plating'which takes-place attheredrawing operation, thus. givingto the -final,-redrawn wire a specialquality which cannot be obtained by plating on fine wire without. suchredrawing.after Plating.

It isthe object -of-the----present invention to provide a method andapparatus whereby from two to five thousand-poundsof plated wire can beproduc'edafdayand whereby a heavy coat or plating-can 'be obtairied inany practical thickness without'appreciable reduction of production andquality'of theproduct.

It is a further object of the present invention provide 'a; method andapparatus whereby relatively high gauge wire can be continuously andefficiently mtal plated.

It isa further object of' the present invention to provide" a method'andapparatus whereby coiled wire may wbe run' at high'speed through aseries of treatments} v It'isa further object'of the present inventionto provide a method and apparatus whereby coiled wire may be run ath'ighspeed through an electroplatingrbathandelectroplated at a speed farinexcess" of any previous speed of travel of wire throughelectroplating; baths.

-It is:a*fur-ther:object of the present invention to provide-a" methodof and'apparatus for electroplatingmetalfbodi'es such as relativelyheavy wirecontinuous'ly and in such away as to prevent oxidation'duringrthe process.

It is-a further. object of the present invention toprovide a'novelmethod and apparatus for electroplating, 'metal bodies -of the classdescribed continuously and to provide continuously thereon a sequence orplurality of platings of the same or different metals. ,j.

Further objectsof. my invention will be apparent from' -a; consideration-of-,- the drawings and specific description hereinafter setforth.

The objects of this invention are accomplished by moving {a coilcontinuously and rapidly forward by resting the: loose" coil on arotating smooth shaft which, for'example, can be a rubber-coated-shaft;therotation of the shaft and the-frictional contact'of the rotatingshaft with the coil actingf-Iinconjunctionwith the springcharacteristic'of' the-wir'e'coilso'that the coil is rotated by therotating shaft and moves forward by reasonof'its'helical' position andits rotation. In the-drawings, 1

Figure I is a side view and partial cross-section of'the apparatus ofthe present invention.

Figure" 2 is across-section taken along the line 22 of"Fig-ure 1-and'showing means by which the spacingfof-t'he'coil is determined andfixed fortravelling through the baths.

Figure 3' is "a cross-section taken along the line 3-3 of Figure l andshows a cross-section of the electroplating tank.

- Itis 'a' fact that'the'faster the wire travels, the more 'efiicientand effectiveis'the'plating operation This is both becausethe speed ofthe wire most effectively moves the plating solution in the immediatevicinity of the wire and therefore most effectively replenishes thatsolution and also because the film of hydrogen gas formed at the platingsurface is most effectively dissipated by a fast travelling wire.

The present method and apparatus are particularly and unusuallyefiicient because a heavy gauge wire is employed and hence a higher loadof electrical current can be imparted to the operation. More current isused and more wire surface is available for the operation. Hence, abetter and faster plating operation can be performed.

Because the operation is continuous and it is not necessary, forexample, to dip the coil intermittently in one bath and then withdraw itto another bath by manual or mechanical operation, a plurality orsequence of the same or different metals may be applied effectively.This is because by either spraying solution on the wire as it emergesfrom one plating bath to the other, or by total immersion of the wire inthe plating bath during the succession of bath after bath without manualor mechanical handling durin its path of travel, oxidation is completelyprevented.

It is of importance in certain cases to avoid such oxidation, forexample, if copper is to be plated and to be treated after plating withhydrogen, since such hydrogen chemically unites with the oxide and formsbubbles filled with water vapor underneath the surface and renders theprotection of the wire inefficient.

This process may be used for coating any kind of metal such a nickel,silver, copper, iron, or certain alloys of any metallic wire, such asiron, copper, steel or alloys regardless of the crosssectional shape,such as fiat, oval, triangular, rectangular, square, octagon or anypolygonal shape.

Referring now more specifically to the drawings in Figure 1 we show ashaft I which is generally circular in cross section as can be seen inFigures 2 and 3. The shaft ID has a rubber cover II on the surfacethereof. The shaft through a gear I3 driven by some suitable source ofpower, not shown.

A coil of wire I2, which, for example, may be copper wire of from A to1" in diameter and although but a few strands of copper wire I2 areshown at the left or introductory end of the machine, it will beunderstood that a coil of such wire can and usually is hung on shaft IE3at this point for introduction into the machine.

It will be recognized by those skilled in the art that wire or metalbodies having a thickness of from A; to 1" could not be led down andaround guide members for travelling through a path since this wouldinvolve a pliability that metal of this thickness does not have for thistype of operation. The wire I2 has a sprin or life to it such as iscommon in coiled Wire of this dimension and plays an important part inits movement through the apparatus. The wire I2 passes over and alongthe shaft I0 because of the rotation of the shaft I 9 and its contactwith the shaft i0 is maintained and facilitated by the roller I5 whichas will be noted in Figures 2 and 3 is circular in cross-section and mayhave a rubber cover It. The function of the roller I5 as stated ismerely to maintain the wire I2 against the rotating shaft I0 and theroller I5 is not power driven. Depending on the spring of the wire I2downward pressure can be exerted on the roller I5 by means of pressureadjusting elements I1 I I) is rotated and I8 which are screw pressuremembers, although equivalents thereof may be employed.

So that the shape of the wire coil I2 may be relatively predetermined inits travel through the baths, guide members and 2| which comprisegrooved roller uides 22 and 23 fixed by bolts 24 and 25 respectively,are so positioned as to shape the wire coil I2 to a givencross-sectional shape by their action in pressing the wire down towardsthe shaft It. To guide the wire and to maintain its loops and its properspaced relation, we provide a comb guide 27 having slots 28 throughwhich the wire passes. The treating baths which will be morespecifically described hereinafter comprise a tank 30 with a series ofpartitions 3I to comprise separate and independent baths for treatingthe wire during its travel. The electroplating tank generally denoted as33 is specifically seen in cross-section in Figure 3. Current issupplied through anodes 34 and 35, the current travelling through theelectrochemical bath 36 through the wire 2 to the cathode roller contact31 supported in a bracket 38 and thence through conductor 39. Thecontact roller cathode 31 is grooved so as to ride firmly on the wireI2. This function is assisted by the roller guide 40. The wire I2 ismaintained at the bottom of the tank in its proper relation by the guideelements formed by the spacer 4| mounted on the rods 42 and A3. Spacer4| may comprise some electrical insulating material and the rods 42 and43 are preferably covered with loosely mounted roller sleeves 44 and 45as shown in Figure 3 which sleeves may be of porcelain or some otherelectrically and chemically inert material.

The wire I2 then travels through a series of subsequent treatment baths46, ll and then out and over the terminal end portion of the shaft I I]which is denoted as 50.

Specifically in the method of the present invention the shaft i0 isrotated through the gear I3 and the rotation of the shaft Ill by reasonof friction which is a slipping but constantly applied friction causesthe wire coil I2 to rotate over the shaft I0 and hence because of thehelical nature of the coil I2 it moves through the machine over theshaft I0 and through the various treatment baths. The rider roll I5resting on the wire I2 maintains it in contact with the shaft in andthus affords the full use of the rotating effect of the shaft II on thewire coil I2. The guide slots 28 in the comb guide 21 serve to space andposition the wire so that it enters and departs from the various bathsin a predetermined manner.

After the various pretreatments of cleaning and the like which are giventhe wire it enters the electroplating bath 33. There through the anodeis imparted a direct current of about from 3-10 volts depending on thegauge of the wire which as pointed out hereinbefore may run from A or upin diameter. The current travels on through the bath through the Wireout through the plurality of cathode contacts 31, the current density ofthe plating ranging from 5 to amps per square decimeter of cathode. Thespeed of travel of the wire coil is extremely flexible and may be asfast as desired. The speed for example can range from 15 feet per minuteup to hundreds of feet per minute.

It is a fact that the faster the wire travels the more efficient andeffective is the plating operation. This is both because the speed ofthe wire most effectively moves the plating solution in the immediatevicinity of the wire and therefore most effectively replenishes thatsolution and also because the film of hydrogen gas formed at the platingsurface is most effectively dissipated by a fast travelling wire.

The present method and apparatus are particularly and unusuallyefficient because a heavy gauge wire is employed and hence a higher loadof electric current can be imparted to the operation. More current isused and more wire surface is available for the operation. Hence abetter and faster plating operation can be performed.

Because the operation is continuous and it is not necessary, forexample, to clip the coil intermittently in one bath and then withdrawit to another bath by manual or mechanical operations, a plurality orsequence of the same or different metals may be applied effectively.

The ordinary electrochemical plating bath of commerce may be employedand for example the plating solution may comprise nickel chloride,copper sulphate, silver cyanide, or any other of the common platingbaths.

Before the plating operation and to prepare the wire for the platingoperation the wire is cleaned by passing it through a series of baths,namely potassium hydroxide, cyanide, hot water, cold Water, etc.

The thickness of the plating that may be formed ranges from .00001 to ashigh as desired. A plating of from .001% thickness to 50% thickness ofthe body to be plated may be formed.

The end products of this process may be drawn down by the ordinary wiredrawing device to as fine a gauge as is desired. The plating formedoriginally when drawn is unimpaired and exceedingly ductile so that itmay be hammered or worked without cracking or breaking. This property inthis respect is markedly superior to platings applied to fine gauge Wiredirectly previous to this invention.

In addition to plating wires, tubes of small diameter may be formed bythis method of plating metal on to some suitable base material and thenremoving the plated metal therefrom.

It will be understood that those skilled in the art may modify theapparatus and method here disclosed in various ways for differentspecific treatments and wire or tube handling problems. The principlesof this invention however are specifically exampled herein and the scopeof the invention is to be limited not by the examples set forth but bythe appended claims.

We claim:

1. An apparatus for electroplating helically formed, elongated, heavygauge metal material comprising a longitudinal series of tanks includinga tank adapted to contain a cleansing solution and a tank adapted tocontain an electroplating solution, a cylindrical roller extending aboveand along the length of the series of tanks, means for rotating saidcylindrical roller, said cylindrical roller adapted to hold a helicalseries of coils of said elongated metal material to be plated so thatthe portions of the coils below the roller are suspended within thetanks, a second cylindrical roller for pressing each of the coils whichare above said tanks at those portions of the coils which contact theupper surface of the first cylindrical roller against the surface of thesaid first roller so that rapid rotation of the said first cylindricalroller produces rapid rotation of the coils and causes the helix of themetal material to feed into the series of baths at one end and out ofthe series of baths at the other end and so that each coil is rolledunder pressure as it emerges from the bath liquid, said tanks beingclosely spaced so that each coil of the helix has its lower portionsubmerged in one of the tanks, and electrical contact means adapted toride on the coils above the surface of the electroplating tank.

2. An apparatus for electroplating helically formed, elongated, heavygauge metal material comprising a longitudinal series of tanks includinga tank adapted to contain a cleansing solution and a tank adapted tocontain an electroplating solution, a rubber surfaced cylindrical rollerextending above and along the length of the series of tanks, means forrotating said cylindrical roller, said cylindrical roller adapted tohold a helical series of coils of said elongated metal material to beplated so that the portions of the coils below the roller are suspendedwithin the tanks, a second cylindrical roller for pressing each of thecoils which are above said tanks at those portions of the coils whichcontact the upper surface of the cylindrical roller against the rubbersurface of the said first roller so that rapid rotation of the saidfirst cylindrical roller produces rapid rotation of the coils and causesthe helix of the metal material to feed into the series of baths at oneend and out of the series of baths at the other end and so that eachcoil is rolled under pressure as it emerges from the bath liquid, saidtanks being closely spaced so that each coil of the helix has its lowerportion submerged in one of the tanks, and electrical contact meansadapted to ride on the coils above the surface of the electroplatingtank.

ETIENNE L. A. CAMIN. HERBERT KENMORE.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 189,533 Wallace et al Apr. 10,1877 241,741 Smith May 17, 1881 351,946 Turnbull Nov. 2, 1886 638,917Emerson Dec. 12, 1899 799,860 Meaker Sept. 19, 1905 1,157,288 Blau Oct.19, 1915 1,601,642 Parker Sept. 28, 1926 2,266,605 Jones et al Dec. 16,1941 2,359,095 Elder et al Sept. 26, 1944 FOREIGN PATENTS Number CountryDate 132,457 Germany July 17, 1902 244,582 Germany Mar. 13, 1912 565,764Germany Dec. 7, 1932 638,552 Germany Nov. 17, 1936

1. AN APPARATUS FOR ELECTROPLATING HELICALLY FORMED, ELONGATED, HEAVYGUAGE METAL MATERIAL COMPRISING A LONGITUDINAL SERIES OF TANKS INCLUDINGA TANK ADAPTED TO CONTAIN A CLEANSING SOLUTION AND A TANK ADAPTED TOCONTAIN AN ELECTROPLATING SOLUTION, A CYLINDRICAL ROLLER EXTENDING ABOVEAND ALONG THE LENGTH OF THE SERIES OF TANKS, MEANS FOR ROTATING SAIDCYLINDRICAL ROLLER, SAID CYLINDRICAL ROLLER ADAPTED TO HOLD A HELICALSERIES OF COILS AND SAID ELONGATED METAL MATERIAL TO BE PLATED SO THATTHE PORTIONS OF THE COILS BELOW THE ROLLER ARE SUSPENDED WITHIN THETANKS, A SECOND CYLINDRICAL ROLLER FOR PRESSING EACH OF THE COILS WHICHARE ABOVE SAID TANKS AT THOSE PORTIONS OF WHICH ARE ABOVE SAID TANKS ATTHOSE PORTIONS OF THE COILS WHICH CONTACT THE UPPER SURFACE OF THE FIRSTCYLINDRICAL ROLLER AGAINST THE SURFACE OF THE SAID FIRST ROLLER SO THATRAPID ROTATION OF THE SAID FIRST CYLINDRICAL ROLLER PRODUCES RAPIDROTATION OF THE COILS AND CAUSES THE HELIX OF THE METAL MATERIAL TO FEEDINTO THE SERIES OF BATHS AT ONE END